Cognitive Sciences Stack Exchange is a question and answer site for practitioners, researchers, and students in cognitive science, psychology, neuroscience, and psychiatry. It's 100% free, no registration required.

I'm trying to create an iPhone app for music therapy (or other kinds of experimental therapy). Such app would help a music therapist keep track of sessions and evaluate progress. One of the issues that I'm facing is evaluating the effects of therapy - I would like the user to rate their "well being" before the session and immediately following the session using iPhone screen.

I want the rating process to be a one tap operation - I'm thinking of producing an X-Y like graph with two axis and letting the user tap on the chart to rate their well being.

While I can create my own graph like that (for example thought(positive/negative)/action(no desire to act/desire to act)). I'm wondering:

Is there a more scientifically accepted or validated scale of well-being that does not involve extensive questionnaires?

If there are no such axis, can you suggest which other metrics I may use in an app like that.

I.e., well-being is measured as a combination of high positive affect, low negative affect, and high life satisfaction. Of course, there are many other measures of subjective well-being (for a review, see Kahneman and Krueger, 2006).

When to use single item and when to use multiple item

In general there are trade-offs in research. More items brings greater reliability but it also takes more time, which can potentially reduce participation or lead to other costs.

A single item measure of well-being might be appropriate when:

measuring the construct reliably is not that important

You are concerned with population level estimates and you have large sample sizes per group

You are doing experience sampling research where you are getting tens or hundreds of observations of well-being at different time points, and thus, participant fatigue is a major issue.

In your case, you are conducting a pre-post study to assess the effect of an intervention. In such cases, it would really be worth administering a reliable multi-item measure of well-being. For example, to complete the PANAS plus Diener Life Satisfaction combination above, might only take a couple of minutes. For the sake of getting reliable measurement, that seems like a valuable use of two minutes.

Affective grids

That said, if you still wish to explore single item measures, check out this previous answer on where Gaël Laurans mentions Russel et al 1989 and Larsen et al 2009 as useful sources: